There is known a suction stage for sucking a substrate such as a wafer.
Such a suction stage is used in e.g. a substrate lamination step in manufacturing a semiconductor device (see, e.g., Patent Literature 1).
In the substrate lamination step, the lamination surfaces of two substrates are laminated to each other to form one substrate.
For instance, the lamination surfaces of two substrates are laminated to each other to form one substrate in the case of e.g. manufacturing what is called an SOI (silicon on insulator) wafer and bonding a glass substrate to a silicon substrate by anode bonding technique.
According to such techniques, substrates can be laminated to each other without interposing e.g. an adhesive between the substrates. This can diversify the process condition in the treatment after lamination (such as plasma treatment, heat treatment, and chemical treatment). Furthermore, this can facilitate e.g. p-n junction and embedding of an insulating film.
However, deformed substrates such as warped substrates are difficult to laminate accurately.